The present invention relates to suction tubes for removing fluids from the gastrointestinal tract. More particularly, the present invention concerns novel tubes so arranged as to avoid sucking up the linings of the stomach and the complications which arise therefrom.
In patient care, it is frequently necessary to remove secretions from within the gastrointestinal tract on a continuing basis. Following intestinal surgery, for example, normal gastrointestinal function is temporarily impaired and the stomach then tends to fill up with gastric secretions and air. The patient consequently becomes distended and nausea and vomiting will ensue. This distention and vomiting can disrupt healing anastamoses and prolong the gastric ileus. Patients suffering from intestinal obstruction likewise will experience vomiting in the natural effort to rid the stomach of accumulated liquids and air. In these patients it is essential to aspirate out the secretions and swallowed air to prevent further distention of the intestines and avoid the complications of spontaneous perforation or gangrene of the intestines. This aspiration is also a mainstay of initial therapy in patients with intestinal obstruction.
The use of suction tubes to evacuate fluids from within the body, for these and other purposes has long been known in the prior art. The so-called "Levin tube", which is even today the most widely used gastric suction tube, was described by A. L. Levin in 1921. "New Gastroduodenal Catheter", Journal of the American Medical Association, Volume 76, p. 1007, 1921. The Levin tube is a long, flexible, single-lumen tube adapted to be introduced into the stomach through the nasal passages and the esophagus. A number of ports for communicating gastric fluids to the interior of the tube are arranged longitudinally adjacent the distal end of the tube. Upon the application of suction to the proximal end of the tube, therefore, stomach fluids are removed through the ports and the interior of the tube to a collection vessel.
The stomach lining or mucosa sits loosely in folds throughout the interior of the stomach and is easily separated from the underlying layers. The medical profession has long recognized that the ports of the single-lumen tube are liable to be blocked by the mucosa when suction is being applied to the tube. See for example, G. Cleland, "A Gastric Aspiration-Tube", The Lancet, Oct. 29, 1955, pp. 908-909; R. K. Hughes et al., "Gastric sump drainage with a water seal monitor", Surgery, Volume 61, No. 2, February, 1967, pp. 192-195; and E. F. Schmerl et al., "Porthole Ulcers Associated with Gastric Intubation", The Western Journal of Medicine, Volume 124, February, 1976, pp. 172-173. These authors all report a causal link between tube blockage by the gastric mucosa and the development of traumatic ulcers during such intubation. The consequences may be limited to pain and discomfort, but patients can also suffer serious blood loss from mucosal ulcerations.
Accordingly, the medical profession has long felt the need to provide a suction tube which avoids the foregoing disadvantages of the single-lumen tube. One proposed solution is to provide a double-lumen tube wherein a partial vacuum is applied to one lumen to remove gastric fluids. A second lumen or sump opens into the first lumen permitting a flow of air into the first lumen adjacent the distal end. It is intended that by introducing this flow of air into the first lumen, the vacuum created when the mucosa is sucked into its ports will be broken.
However, it has been reported that ulceration of the mucosa occurs, nevertheless, following intubation with a double-lumen tube. J. F. Greene, Jr., et al., "Gastric Ulceration: A Complication of Double-Lumen Nasogastric Tubes", Journal of the American Medical Association, Volume 224, No. 3, April 16, 1973, pp. 338-339. Greene et al. report four cases in which autopsies revealed superficial gastric ulcers spacially arranged identically to the sucking ports of the double-lumen nasogastric tube, and concluded that this ulceration was caused by sucking the mucosa into the lumen.